Okla. Stat. tit. 6, § 6-1710
Authority to operate trust business
A state trust company or a state bank may:
1. Perform any act as a fiduciary;
2. Engage in any trust business; and
3. Exercise any incidental power that is necessary to enable it
to fully exercise, according to commonly accepted fiduciary customs
and usages, a power conferred in this act.